The most portable method for configuring the client is to use a CFC to place your config settings in much like our other libraries such as WireBox and CacheBox allow.
To do this simply create a plain CFC with a public method called configure(). Inside of that method, put your config settings into the variables scope of the component. The configure() method does not need to return any value. It will be automatically invoked by the SDK prior to the config settings being extracted from the CFC.